Anchor Bolt Spacing - Transmission Poles

[reed0519]

A vendor designed the anchor bolts for a pair of steel transmission poles with the AB (2.25") spacing at 6" center to center. I have another engineer telling me this spacing violates ACI-318 17.7.1 of min 4*da. ASCE 48-11 doesn't provide any guidance on this. I have seen several places where an AB spacing of 6" is used for 2.25" anchor bolts. I'm not an ACI code expert, but where does the code allow for this? I see 17.7.4, but not sure where to go from there. Any help would be greatly appreciated.

 

[msquared48]

Is he saying that you cannot have the AB closer than 9" then?

Mike McCann, PE, SE (WA)

 

[reed0519]

Yes, that's correct.

 

[msquared48]

Did you check to see if there is any guidance in TIA 222G?



Mike McCann, PE, SE (WA)

 

[hokie66]

I don't know why ACI318 should apply to power poles.

 

[canwesteng]

Well, it's a concrete structure, and ACI 318 does say it applies to non building structures. The pdf version has the commentary to the right of the code, that's a good start to figure out if it might apply to your case. The spacing is adequate for concrete placement in any case.

 

[reed0519]

msquared48 - I'll look into TIA 222G.

hokie66 - So ASCE 48-11 rules over ACI 318 in terms of AB design? Even if ACI is used to size the reinforcing steel?

 

[msquared48]

I ran into an applicable code section on the net but lost it... I will keep looking...

Mike McCann, PE, SE (WA)

 

[msquared48]

https://books.google.com/books?id=8...sion Pole minimum Anchor Bolt spacing&f=false

Ran across another reference that used ASCE 48-11 for AB design... Hopefully it copied OK.

Still looking for the other reference...

Mike McCann, PE, SE (WA)

 

[hokie66]

This discusses various standards used for designing poles. No mention of ACI, but it could be referenced by some of the other standards.

http://www.kornegayengineering.com/...stribution-light-poles-whitepaper-acrosby.pdf

 

[msquared48]

I found it, but in looking harder, the article did not apply to the anchor bolt spacing - only the cage steel spacing. Sorry.

Mike McCann, PE, SE (WA)

 

[JedClampett]

I've seen where the tower anchor bolt spacing is small (not violating ACI small) because they just used really long anchor bolts lapping with the reinforcing. For an example, see FDOT High Mast Tower Details.